Danillo Valverde, Herbert C Georg, Gabriel I Pagola, Patricio F Provasi
{"title":"甘氨酸构象的核磁共振参数、屏蔽和自旋耦合常数分析。","authors":"Danillo Valverde, Herbert C Georg, Gabriel I Pagola, Patricio F Provasi","doi":"10.1021/acs.jpca.4c06527","DOIUrl":null,"url":null,"abstract":"<p><p>In this study, we worked at the CCSD/aug-cc-pVTZ level to obtain the conformers of glycine in its neutral and zwitterionic forms in the gas and water phases. We then computed the NMR properties (spin-spin coupling constants and nuclear magnetic shieldings) at the SOPPA/aug-cc-pVTZ-J level. We attempt to elucidate the apparent discrepancy arising from two previous works by Valverde et al. [<i>J. Chem. Phys.</i>, <b>2018</b>, <i>148</i>, 024305] and Caputo and Provasi [<i>Sci</i>, <b>2021</b>, <i>3</i>, 41]. Our optimized structures align with previous theoretical predictions, although some geometries were not found. Additionally, our results suggest that in the gas phase the Δ <sup>1</sup><i>J</i>(O,C) = <sup>1</sup><i>J</i>(O<sub>cis</sub>,C<sub>O</sub>) - <sup>1</sup><i>J</i>(O<sub>trans</sub>,C<sub>O</sub>) is positive when the acid group is in the <i>trans</i> conformation and negative in the <i>cis</i> conformation; however, this trend is not well reproduced in water. From magnetic shielding calculations, we cannot distinguish between an O-H in the <i>cis</i> or <i>trans</i> conformation.</p>","PeriodicalId":59,"journal":{"name":"The Journal of Physical Chemistry A","volume":" ","pages":"686-694"},"PeriodicalIF":2.7000,"publicationDate":"2025-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Analysis of the NMR Parameters Shielding and Spin-Spin Coupling Constants of Glycine Conformers.\",\"authors\":\"Danillo Valverde, Herbert C Georg, Gabriel I Pagola, Patricio F Provasi\",\"doi\":\"10.1021/acs.jpca.4c06527\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p><p>In this study, we worked at the CCSD/aug-cc-pVTZ level to obtain the conformers of glycine in its neutral and zwitterionic forms in the gas and water phases. We then computed the NMR properties (spin-spin coupling constants and nuclear magnetic shieldings) at the SOPPA/aug-cc-pVTZ-J level. We attempt to elucidate the apparent discrepancy arising from two previous works by Valverde et al. [<i>J. Chem. Phys.</i>, <b>2018</b>, <i>148</i>, 024305] and Caputo and Provasi [<i>Sci</i>, <b>2021</b>, <i>3</i>, 41]. Our optimized structures align with previous theoretical predictions, although some geometries were not found. Additionally, our results suggest that in the gas phase the Δ <sup>1</sup><i>J</i>(O,C) = <sup>1</sup><i>J</i>(O<sub>cis</sub>,C<sub>O</sub>) - <sup>1</sup><i>J</i>(O<sub>trans</sub>,C<sub>O</sub>) is positive when the acid group is in the <i>trans</i> conformation and negative in the <i>cis</i> conformation; however, this trend is not well reproduced in water. From magnetic shielding calculations, we cannot distinguish between an O-H in the <i>cis</i> or <i>trans</i> conformation.</p>\",\"PeriodicalId\":59,\"journal\":{\"name\":\"The Journal of Physical Chemistry A\",\"volume\":\" \",\"pages\":\"686-694\"},\"PeriodicalIF\":2.7000,\"publicationDate\":\"2025-01-23\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"The Journal of Physical Chemistry A\",\"FirstCategoryId\":\"1\",\"ListUrlMain\":\"https://doi.org/10.1021/acs.jpca.4c06527\",\"RegionNum\":2,\"RegionCategory\":\"化学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"2025/1/9 0:00:00\",\"PubModel\":\"Epub\",\"JCR\":\"Q3\",\"JCRName\":\"CHEMISTRY, PHYSICAL\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"The Journal of Physical Chemistry A","FirstCategoryId":"1","ListUrlMain":"https://doi.org/10.1021/acs.jpca.4c06527","RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2025/1/9 0:00:00","PubModel":"Epub","JCR":"Q3","JCRName":"CHEMISTRY, PHYSICAL","Score":null,"Total":0}
Analysis of the NMR Parameters Shielding and Spin-Spin Coupling Constants of Glycine Conformers.
In this study, we worked at the CCSD/aug-cc-pVTZ level to obtain the conformers of glycine in its neutral and zwitterionic forms in the gas and water phases. We then computed the NMR properties (spin-spin coupling constants and nuclear magnetic shieldings) at the SOPPA/aug-cc-pVTZ-J level. We attempt to elucidate the apparent discrepancy arising from two previous works by Valverde et al. [J. Chem. Phys., 2018, 148, 024305] and Caputo and Provasi [Sci, 2021, 3, 41]. Our optimized structures align with previous theoretical predictions, although some geometries were not found. Additionally, our results suggest that in the gas phase the Δ 1J(O,C) = 1J(Ocis,CO) - 1J(Otrans,CO) is positive when the acid group is in the trans conformation and negative in the cis conformation; however, this trend is not well reproduced in water. From magnetic shielding calculations, we cannot distinguish between an O-H in the cis or trans conformation.
期刊介绍：
The Journal of Physical Chemistry A is devoted to reporting new and original experimental and theoretical basic research of interest to physical chemists, biophysical chemists, and chemical physicists.
求助内容：
应助结果提醒方式：
京公网安备 11010802042870号
